Later in the year she was trusted to bring Harry the time and place of Albus Dumbledore's next private lesson with Harry, and also a note from Severus Snape that stated he will be doing his detention no matter how many party invitations he had received, and that he would be sorting out fresh Flobberworms from rotten ones, without the use of protective gloves. At the end of this academic year Albus Dumbledore was murdered on school grounds by Severus Snape.

Battle of Hogwarts

In last few months of the school year the Second Wizarding War came to a close with the Battle of Hogwarts. Lord Voldemort and his Death Eater army invaded the castle and a battle broke out to defend it and protect Harry Potter. The castle was almost completely destroyed and there were many casualties. It is unknown if Demelza was present for the battle or if she was too young to stay in combat.